I personally am a fan of the following ideas:
1. Cheval De Frise stuck in the down position, it provides the challenge of not going so fast or slow that might cause your bot to tip over, (plus the airtime photos are going to be great
)
2. Or a custom made variant of the cheval de frise ramp idea, so that teams can go over it from both sides, and not just one.
3. Somehow stick boulders in the defense base/holder, so a bot would have to drive over the boulders. Challenge is to not get stuck.
I really don't like the idea of having an empty defense with no points. Because once the other 4 defenses are knocked out, than shooter bots will just traverse the outer works using the empty defense, making it way too easy....
plus 3 ball auto anyone?. And also, that completely negates the effect of the secret passage.. (okay not completely, but still).